Logging grapple

ABSTRACT

A log skidding tractor has a grapple-positioning boom mounted thereon. A cable-operated grapple is releasably coupled to the boom and is placed into log grasping positions by the boom. A cable for closing the tongs of the grapple is connected to a winch mounted on the tractor, which winch is operated to tension the cable and close the grapple. A latch mechanism on the grapple holds the tongs closed and permits the cable tension to be relaxed whereby the grapple may be released from the boom and the tractor may be driven to a more favorable position for skidding the load held by the grapple.

Ranstord et a1.

LOGGING GRAPPLE Inventors: Neil Edward Ransford, Dubuque,

Iowa; Leland Glen Gilbert, Moerfelden, Germany; Richard Herman Hunger,Dubuque, Iowa Deere & Company, Moline, 111.

Oct. 12, 1971 (Under Rule 47) Appl. No.: 188,397

Assignee:

Filed:

11.5. C1. 294/112, 212/7, 214/147 G lint. Cl. 1866c 1/42 Fleld 01 Search294/106, 108, 111, 294/112; 37/183 R, 183 A, 186, 187,188; 212/7, 55;214/147 R, 147 AS, 147 G, 92

References Cited UNITED STATES PATENTS Dec. 25, 1973 3,099,476 7/1963Miller 294/112 2,025,340 12/1935 Crocker 3,082,031 3/1963 Lindberg294/111 Primary Examiner--Evon C. Blunk Assistant ExaminerJohnny D.Cherry Attorney-H. Vincent Harsha et al.

[ ABSTRACT A log skidding tractor has a grapple-positioning boom mountedthereon. A cable-operated grapple is releasably coupled to the boom andis placed into log grasping positions by the boom. A cable for closingthe tongs of the grapple is connected to a winch mounted on the tractor,which winch is operated to tension the cable and close the grapple. Alatch mechanism on the grapple holds the tongs closed and permits thecable tension to be relaxed whereby the grapple may be released from theboom and the tractor may be driven to a more favorable position forskidding the load held by the grapple.

15 Claims, 7 Drawing Figures PAIENTEDuzczsmn 3.781.056 sum 10F s FIG.I

1N VENTORS RICHARD H. HUNGER NEIL E. RANSFORD LELAND G. GlLBERTPAIENIEDuaczs 1925 L 378L056 SHEET 2 or 5 I N VEN TORS RICHARD H. HUNGERNEIL E. RANSFORD LELAND G. GILBERT PAIENIEI] DEC 25 I975 SHEET 30F 5INVENTORS RICHARD H. HUNGER NEIL E. RANSFORD LELAND G. GILBERTPATENTEUUEBZS I925 3.781; 056

SHEFT u 0F s INVENTORS RICHARD H. HUNGER NEIL E. RANSFORD LELAND G.GILBERT PATENTED-HEBZS ms SHEET 5 [IF 5 FIG.5

. INVENTORS RICHARD H HUNGER NEIL E. RANSFORD LELAND G. GILBERT LOGGINGGRAIPPLE BACKGROUND OF THE INVENTION The present invention relates to alogging grapple and more particularly relates to a cable-operatedgrapple having means for latching the tongs closed on a load so that theload will be tightly gripped even when the operating cable is not intension.

The current trend in apparatus for skidding felled trees in and from thewoods to a landing is toward a type including an articulated loggingtractor equipped with a boom from which a grapple is releasablysuspended. In these apparatus, the boom properly positions the grapplefor grasping one or more trees adjacent an end thereof. The tree end orends are then elevated from the ground and the remainder of the load isskidded. A length of cable is connected between a winch on the tractorand the grapple and if the tractor encounters undesirable tractive orstability conditions, the grapple and its load are dropped permittingthe tractor to be maneuvered to a more desirable location. The winch isthen operated to retrieve the grapple and its load.

The current grapples, however, do not have an effective means forkeeping a grip on the trees in a load once the grapple is dropped. As aresult, the largest load a skidder can now pick up is limited by theoperators confidence that he can deliver the load to a landing withoutundue difficulty.

SUMMARY OF THE INVENTION According to the present invention there isprovided a novel cable-operated grapple and, more particularly, there isprovided a grappel which is especially adapted for log skiddingoperations.

An object of the invention is to provide a compact pulley and cablearrangement for closing the tongs on a load and for keeping the grapplein a proper attitude when the grapple is being retrieved.

Another object is to provide releasable latch means for locking thetongs on a load.

Still another object is to provide a latch, as described above, which isremotely controllable from the operators station.

These and other objects will become apparent from the ensuingdescription and the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a side view of a loggingapparatus in which the present invention is embodied, and showing partsremoved for clarity.

FIG. 2 is an enlarged front elevational view of the grapple shown inFIG. I, with the grapple being illustrated in a condition wherein thetongs are at an intermediate position.

FIG. 3 is a view similar to FIG. 2 but showing the FIG. 7 is atop planview of the pulley and a cable arrangement as it would appear in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, thereis shown a logging apparatus indicated in its entirety by the referencenumeral 10. The apparatus 10 includes a conventional logging tractor 12including front and rear sections 114 and 16, respectively,interconnected by a pivot structure 18, permitting articulation betweenthe sections. Located on the front section 14 is an operators stationwhereat the controls for the logging apparatus are found.

The rear tractor section 16 includes a frame 22 on which a winch 24 iscentrally mounted directly behind the pivot structure I8. A cable 26 iswound about the winch 24 and extends rearwardly to a fairlead 28, thatis fixed centrally at the rear of the frame 22. The fairlead 28 includesa transverse roller 30 rotatably mounted in its upper end and the cable26 passes over the roller 30. A butt pan 31 is fixed to the rear of theframe 18 in a location generally vertically below the roller 30.

Also mounted on the frame 18 is a boom 32, which includes a pair ofparallel inner arms 34 (only one shown) disposed in straddlingrelationship to the fairlead 28 and pivoted at their lower ends forfore-and-aft swinging. Selective swinging is accomplished bysimultaneous operation of a pair of hydraulic actuators 36 (only oneshown) respectively pivotally interconnected between the pair of arms 34and the frame 22. A transverse cross-member 38 is pivotally received inthe outer ends of the arms 34 for rocking about a horizontal axis. Forthis purpose, a crank arm 40 is fixed to the member 38 and a hydraulicactuator 42 is pivotally interconnected between the arm 40 and the frame22. An outer boom arm 44 is pivoted, as at 46, to the crossmember 38 forlateral swinging and a hydraulic actuator 48 is pivotally interconnectedbetween the crossmember 38 and the arm 44 for selectively adjusting thelatter. Thus, it can be seen that the boom 32 may be positioned tovarious positions relative to the frame 18 through selective actuationof the pair of actuators 36, the actuator 42 and the actuator 48.

Fixed to the outermost end of the boom 32 is a releasable connector 50including a pair of opposed jaws 52 and 54. The jaw 52 is hinged forswinging movement toward and away from the jaw 54 and a hydraulicactuator 56 is pivotally interconnected between the jaw 52 and the arm44 for accomplishing such movement.

Releasably suspended from the connector 50 is a grapple 58. The grapple58 includes a yoke 60 including a pair of fore-and-aft spaced, parallel,transversely extending, inverted V-shaped members 62 and 64 having aswivel 66 pivotally received in the apices thereof. A lost motionconnection is formed between the yoke 60 and the connector 50 throughmeans of a rod 68, which is slidably received in the swivel 66, for apurpose explained below. A ring is pivotally received in the upper endof the rod 68 and is captively but loosely held by the connector 50. Therod 68 includes a shoulder 71, adjacent the lower end thereof, whichkeeps the rod from being withdrawn from the swivel 66 and which abutsagainst the bottom of the yoke 60, when the grapple is suspended fromthe boom 32.

A pair of opposed, right andd left tongs 72 and 74, respectively, asviewed in FIG. 2, are located below the yoke 60 and are symmetricallyspaced relative to a longitudinal vertical plane passing through theapex of the yoke 60. As can best be seen in FIG. 1, the tong 72 inlcudesa pair of forward and rear plates 76 and 78, and the tong 74 includes asimilarly disposed pair of plates 80 and 82. The plates 76 and 78, ofthe tong 72, have respective parallel, arcuate, inner and outer edges,which converge from top to bottom. The plates 76 and 78 areinterconnected by inner and outer arcuate straps 84 and 86, whichrespectively extend adjacent said inner and outer edges and terminateshort of the upper ends of the plates 76 and 78. A channel member 88 isfixed between the plates 76 and 78 with its legs against the upperportion of the inner strap 84 and with its web forming a continuation ofthe upper end of the outer strap 86.

The plates 80 and 82 of the tong 74 are a mirror image of the plates 76and 78 and are similarly interconnected to each other by inner and outerstraps 90 and 92 and by a channel member 94. It is to be noted that thelower ends of the rear plate 78 of the tong 72 and the forward plate 80of thetong 74 are offset, respectively forwardly and rearwardly fromtheir upper ends, a distance permitting the lower ends of the tongs 72and 74 to assume overlapped positions, such as the fully closed positionillustrated in FIG. 4.

A pair of like links 96 and 98 have their upper ends locatedrespectively between the right and left ends of the yoke members 62 and64, whereat they are pivotally mounted by means of a pair offore-and-aft pins 100 and 102. The lower end of the link 96 is locatedbetween a pair of cars 104 fixed to the web of the channel member 88 andis pivotally secured thereto by means of a fore-and-aft pin 106.Similarly, the lower end of the link 98 is located between a pair ofears 108 fixed to the web of the channel member 94 and is pivotallysecured thereto by a fore-and-aft pin 110.

As viewed in FIG. 2, the upper end of the tong 72 is provided with apair of fore-and-aft extending, vertically spaced pivot pins 112 and 114and 'the upper end of the tong 74 is provided with a pair offore-and-aft extending, vertically spaced pivot pins 116 and 118.Connected between the upper pivot pin 112 in the tong 72, and the lowerpivot pin 118, in the tong 74, is a first pair of spaced, parallel tielinks 120 which straddle the tongs 72 and 74. Connected between thelower pivot pin 114, in the tong 72, and the upper pivot pin 116, in thetong 74, is a second pair of spaced, parallel tie links 122, theopposite ends of which are located between the tong plates 76 and 78 andbetween the ton plates 80 and 82. The pairs of links 120 and 122 act tocause the tongs 72 and 74 to open and close symmetrically with respectto the longitudinal vertical plane extending through the apex of theyoke 60.

The means for closing the tongs 72 and 74 includes first and secondgenerally horizontal pulley mounting brackets 124 and 126 respectivelypivotally mounted on the lower pivot pins 114 and 118 in the tongs 72and 74. A pair of pulleys 128 and 130 are respectively rotatably mountedon the brackets 124 and 126 in alignment between the tongs 72 and 74.The pulley bracket 126 includes a forwardly extending portion 132 whichis hingedly interconnected with a third pulley bracket 134 which carriesa third rotatably mounted pulley 136. The cable 26 extends around theleft side of the pulley 136, the right side of the pulley 128, the leftside of the pulley and back toward the pulley 128 where its end is fixedat 138 to the bracket 124. Thus, it can be seen that when the winch 24is operated to wind the cable 26 thereabout, the cable will be tensionedand the pulley brackets 124 and 126 will pull the pins 114 and 118towards each other and this action will be transferred through the pairsof tie links 120 and 122 to move the tongs toward the fully closedposition illustrated in FIG. 4.

It should be noted that when the tension in the cable 26 is relaxed, theweight distribution of the tongs 72 and 74, and the members carriedthereby, relative to the pivot pins 106 and 110 will cause the tongs togravitate to the fully open position illustrated in FIG. 3.

A latch 140 is provided for locking the tongs 72 and 74 on a load, whenthe grapple 58 is dropped from the boom 32 and the cable 26 is relaxed.The latch 140 includes a latch arm 142, which is pivoted at one end tothe upper pivot pin 112 in the tong 72 and terminates at its other endin a downwardly directed tang 144. L0- cated between and fixed to thepair of tie links 122 is a plate 146, to the upper face of which isfixed a pluality of teeth 148 shaped to receive the tang 144therebetween. The latch arm 142 is connected to the lower end of the rod68 by means of a link and the tang 144 can be selectively disengagedfrom the teeth 148 by pulling upwardly on the ring 70 through means ofthe boom 32.

In operation, the logging apparatus 10 is readied for moving to alogging site by actuating the winch 24, to wind in the cable 26, and byactuating the hydraulic actuators 36, 42 and 48 to swing the boom 32 totightly position the grapple 58 against the fairlead 28 and the butt pan31. The pulleys 128, and 130 and 136, about which the cable 26 istrained, are all located in a central region of the grapple 58, and thetension in the cable 26 will keep the grapple 58 from swinging relativeto the boom 32.

When the tractor 12 arrives at the logging site, the winch 24 isactuated to relax the cable 26, thus permitting the tongs to gravitateto the fully open position illustrated in FIG. 3. The boom positioningactuators 36, 42 and 48 are then selectively actuated to position thtongs 72 and 74 in straddling relationship to a desired load to beskidded. The winch 24 is then actuated to tension the cable 26 and thistensioning force acts through the pulleys 128 and 130 and theirrespective mounting brackets 124 and 126 to close the tongs 72 and 74upon the load. Thereafter, the boom 32 is raised and the winch 24 isactuated to raise the leading end of the load from the ground andposition it closely adjacent the butt pan 31. It is important to notethat almost the entire weight of the load is borne solely by the cable26 and the fairlead 28 so that a heavily constructed boom is notnecessary and the size of the boom 32 is dictated only by the strengthnecessary to lift the weight of the grapple 58. The thusly loadedtractor 12 is then driven toward a desired landing.

Should the tractor l2 encounter a soft stretch, or a relatively steepincline, along the path to the landing area, it may be desirable ornecessary to drop the load supported by the tractor 12. To do this, thewinch 24 is actuated to permit the grapple 58 to lower to the groundwhile at the same time maintaining sufficient tension in the cable 26 tokeep the tongs closed. The boom 32 is lowered to slide the rod 68downwardly through the swivel 26 to cause the latch arm M2 to be swungtoward the teeth 148 to engage the tang 14-4 therewith. The actuator 56is then actuated to open the jaws 52 and 54 of the connector 50 and theboom 32 is swung away from the ring 70. The winch 24 is then actuated topermit the free unwinding of the cable 26 and the tractor 12 ismaneuvered to terrain having more desirable tractive and/or stabilityqualities. The winch 24 is then actuated to retrieve the grapple 58 andthe load held thereby. Since the latch 140 remains locked duringretrieval of the load, there is little possibility that any of the loadwill slip from the grasp of the tongs. The reliability of the latch 140is enhanced by the fact that the cable 26 is attached to and associatedwith only centrally-located elements of the grapple 58, and thus, tendsto maintain the grapple 58 upright, as it is retrieved, which keeps thering 70 from becoming snagged in undergrowth or obstacles along thelogging trail.

When the grapple 58 is winched in to a position within the reach of theboom 32, the connector 50 is again holdingly engaged with the ring 70.Since the cable 26 is now in tension, the latch 40 may be disengaged andthis is donw merely by raising the boom 32 to pull upwardly on the rod68 and the latch arm 142. The load can then be dropped at a desiredlanding by merely relaxing the cable 26.

We claim:

ll. In combination with a logging vehicle equipped with a winch and aload-elevating means, an improved grapple comprising: a yoke; remotelyactuatable connector means releasably securing said yoke to saidelevating means; a pair of tongs located to one side of said yokeoppositely of said elevating means; link means pivotally suspending saidtongs from said yoke for movement between a spread apart first positionand a log-grappling second position; grapple operating means operativelyconnected to said tongs for moving the same to said second position; andlatch means operatively connected to said tongs and to said elevatingmeans and being actuatable, by said elevating means, between latched andunlatched positions for respectively fixing and releasing said tongs inand from selected positions.

2. The invention defined in claim 1 wherein said elevating meansincludes a boom; and said actuatable connector means interconnectingsaid grapple and said boom.

3. The invention defined in claim 2 wherein said latch means includes alink pivotally interconnected between said tongs and having a pluralityof upwardly facing teeth spaced along the upper side thereof; a latcharm pivotally connected to one of said tongs for swinging movementtoward and away from said teeth and including a tang directed forregister with said teeth; and latch operating means being pivotallyinterconnected between said latch arm and said elevating means and beingresponsive to downward and upward movements of said elevating meansrelative to said yoke for respectively engaging and disengaging saidlatch arm with, and from, said teeth.

4. The invention defined in claim 3 wherein said latch operating meansincludes a rod; a swivel being centrally located on said yoke and saidrod being slidably received in said swivel.

5. The invention defined in claim 1 wherein said latch means includes alink pivotally interconnected between said tongs and having a pluralityof upwardly facing teeth spaced along the upper side thereof; a latcharm pivotally connected to one of said tongs for swinging movementtoward and away from said teeth and including a tang directed forregister with said teeth; and latch operating means being pivotallyinterconnected between said latch arm and said elevating means and beingresponsive to downward and upward movement of said elevating meansrelative to said yoke for respectively moving said latch arm downwardlyand upwardly for respectively engaging and disengaging said latch arm,with and from, said teeth.

6. The invention defined in claim 5 wherein said latch operating meansincludes a rod; a swivel being centrally located on said yoke and saidrod being slidably received in said swivel.

7. The invention defined in claim 1 wherein said grapple-operating meansincludes a pulley and cable means intervening between said tongs andincluding first and second pulley brackets pivotally connectedrespectively to said pair of tongs for movement parallel to the movementof said tongs; first and second pulleys respectively rotatably mounted,in said first and second brackets, about axes extending crosswise tosaid bracket pivot axes; and a cable having one end fixed to one of saidbrackets and being trained about said pulleys and fixed to said winchsuch that when said winch is operated to wind said cable thereabout,said cable is tensioned to cause said grapples to move to said secondposition.

8. The invention defined in claim 7 and further including a third pulleybracket vertically pivotally connected to, and projecting toward saidvehicl from, one of said first and second pulley brackets; a thirdpulley rotatably mounted in said third bracket about an axis extendingcrosswise to said third bracket pivot axis; and said cable beingguidingly trained on said third pulley.

9. The invention defined in claim 7 wherein the pivot axes on which saidfirst and second pulley brackets are mounted are substantially paralleland coplanar.

lit). in combination with a logging vehicle of the type including awinch, a roller located on the vehicle rearwardly of and in substantialfore-and-aft alignment with the winch, a cable connected to the winchand extending over and terminating in an end located behind the roller,the winch and roller being so positioned relative to each other that thecable portion extending between the cable end and the winch is movedalong a substantially fore-and-aft extending path when the cable end islocated directly behind the vehicle and the cable is being spooled on oroff said winch, and a vertically swingable boom means being located onthe rear portion of the vehicle for raising and lowering loads at therear of the vehicle, an improved grapple comprising: a yoke; remotelyactuatable connector means releasably securing said yoke to said boommeans exclusive of said cable and the operation thereof; first andsecond opposed tongs being spaced to one side of said yoke in adirection opposite from said boom means, link means swingably suspendingsaid tongs from said yoke for movement between a spread apart firstposition and a log-grappling second position; first and second pulleybrackets being respectively pivotally connected to said first and secondtongs for swinging movement respectively about first and second axesextending cross-wise to the direction of movement of said tongs; firstand second pulleys being respectively rotatably mounted in said firstand second pulley brackets for rotation about third and fourth axesextending crosswise to said first and second axes; and said cable endbeing fixed to one of said cable brackets and said cable being trainedabout said first and second pulleys such that said grapple tongs will bemoved towards said log-grappling position upon said cable beingtensioned.

11. The invention defined in claim 10 and further including a thirdpulley bracket vertically pivotally connected to, and projecting towardsaid vehicle from, one of said first and second pulley brackets; a thirdpulley rotatably mounted in said third bracket about an axis extendingcrosswise to said third bracket pivot axis; and said cable beingguidingly trained on said third pulley.

12. The invention defined in claim 10 wherein said first and secondtongs each include adjacent and remote ends relative to the distance ofthe ends from said yoke; said link means pivotally suspending said tongsfrom said yoke comprising first and second link members respectivelyhaving first ends pivotally connected to said yoke and having secondends respectively pivotally connected to said first and second tongs atlocations located adjacent to, but spaced toward said remote ends from,said adjacent ends of said tongs; said first and second pulley bracketsbeing respectively pivotally connected to said first and second tongs atlocations intermediate said adjacent ends and the location whereat thesecond ends of said first and second link members are connected; a firsttie link structure having a first end pivotally connected to theadjacent end of nected to, and projecting toward said vehicle from, oneof said first and second pulley brackets; a third pulley rotatablymounted in said third bracket about an axis extending crosswise to saidthird bracket pivot axis; and said cable being fuidingly trained on saidthird pulley.

14. The invention defined in claim 12 and further including latch meansfor selectively locking said first and second tongs in place; said latchmeans including a plurality of upwardly facing teeth being spaced alongthe length of one of said tie link structures in facing relationship tosaid yoke; a latch member being pivotally connected, at one end to theadjacent end of that tong to which the tie link structure that carriessaid teeth is not connected, for movement toward and away from saidteeth and a tang being formed on said latch member for engagement withsaid teeth; and remotely operable means being connected to said latchmember for selectively moving the latter so as to place said tang intoand out of engagement with said teeth for respectively locking andunlocking said tongs.

15. The invention defined in claim 14 wherein said remotely actuatablemeans comprises a rod; a swivel being pivotally connected to said yokemidway between the locations whereat said first and second links areconnected to said yoke, said swivel having an opening therethroughextending crosswise to the pivotal axis of the block; a rod beingslidable received in said block; a connector ring being pivotallyconnected to an upper end of said rod; a link being pivotally connectedat one end to a lower end of said rod and being pivotally connected atanother end to said latch member; and said remotely actuatable connectormeans being releasably connected to said connection ring, whereby upwardand downward movement of said boom means when the latter is connected tothe connection ring will respectively cause upward and downward movementof said latch member and thereby effect the unlocking and locking ofsaid tongs.

1. In combination with a logging vehicle equipped with a winch and aload-elevating means, an improved grapple comprising: a yoke; remotelyactuatable connector means releasably securing said yoke to saidelevating means; a pair of tongs located to one side of said yokeoppositely of said elevating means; link means pivotally suspending saidtongs from said yoke for movement between a spread apart first positionand a log-grappling second position; grapple operating means operativelyconnected to said tongs for moving the same to said second position; andlatch means operatively connected to said tongs and to said elevatingmeans and being actuatable, by said elevating means, between latched andunlatched positions for respectively fixing and releasing said tongs inand from selected positions.
 2. The invention defined in claim 1 whereinsaid elevating means includes a boom; and said actuatable connectormeans interconnecting said grapple and said boom.
 3. The inventiondefined in claim 2 wherein said latch means includes a link pivotallyinterconnected between said tongs and having a plurality of upwardlyfacing teeth spaced along the upper side thereof; a latch arm pivotallyconnected to one of said tongs for swinging movement toward and awayfrom said teeth and including a tang directed for register with saidteeth; and latch operating means being pivotally interconnected betweensaid latch arm and said elevating means and being responsive to downwardand upward movements of said elevating means relative to said yoke forrespectively engaging and disengaging said latch arm with, and from,said teeth.
 4. The invention defined in claim 3 wherein said latchoperating means includes a rod; a swivel being centrally located on saidyoke and said rod being slidably received in said swivel.
 5. Theinvention defined in claim 1 wherein said latch means includes a linkpivotally interconnected between said tongs and having a plurality ofupwardly facing teeth spaced along the upper side thereof; a latch armpivotally connected to one of said tongs for swinging movement towardand away from said teeth and including a tang directed for register withsaid teeth; and latch operating means being pivotally interconnectedbetween said latch arm and said elevating means and being responsive todownward and upward movement of said elevating means relative to saidyoke for respectively moving said latch arm downwardly and upwardly forrespectively engaging and disengaging said latch arm, with and from,said teeth.
 6. The invention defined in claim 5 wherein said latchoperating means includes a rod; a swivel being centrally located on saidyoke and said rod being slidably received in said swivel.
 7. Theinvention defined in claim 1 wherein said grapple-operating meansincludes a pulley and cable means intervening between said tongs andincluding first and second pulley brackets pivotally connectedrespectively to said pair of tongs for movement parallel to the movementof said tongs; first and second pulleys respectively rotatably mounted,in said first and second brackets, about axes extending crosswise tosaid bracket pivot axes; and a cable having one end fixed to one of saidbrackets and being trained about said pulleys and fixed to said winchsuch that when said winch is operated to wind said cable thereabout,said cable is tensioned to cause said grapples to move to said secondposition.
 8. The invention defined in claim 7 and further including athird pulley bracket vertically pivotally connected to, and projectingtoward said vehicl from, one of said first and second pulley brackets; athird pulley rotatably mounted in said third bracket about an axisextending crosswise to said third bracket pivot axis; and said cablebeing guidingly trained on said third pulley.
 9. The invention definedin claim 7 wherein the pivoT axes on which said first and second pulleybrackets are mounted are substantially parallel and coplanar.
 10. Incombination with a logging vehicle of the type including a winch, aroller located on the vehicle rearwardly of and in substantialfore-and-aft alignment with the winch, a cable connected to the winchand extending over and terminating in an end located behind the roller,the winch and roller being so positioned relative to each other that thecable portion extending between the cable end and the winch is movedalong a substantially fore-and-aft extending path when the cable end islocated directly behind the vehicle and the cable is being spooled on oroff said winch, and a vertically swingable boom means being located onthe rear portion of the vehicle for raising and lowering loads at therear of the vehicle, an improved grapple comprising: a yoke; remotelyactuatable connector means releasably securing said yoke to said boommeans exclusive of said cable and the operation thereof; first andsecond opposed tongs being spaced to one side of said yoke in adirection opposite from said boom means, link means swingably suspendingsaid tongs from said yoke for movement between a spread apart firstposition and a log-grappling second position; first and second pulleybrackets being respectively pivotally connected to said first and secondtongs for swinging movement respectively about first and second axesextending cross-wise to the direction of movement of said tongs; firstand second pulleys being respectively rotatably mounted in said firstand second pulley brackets for rotation about third and fourth axesextending crosswise to said first and second axes; and said cable endbeing fixed to one of said cable brackets and said cable being trainedabout said first and second pulleys such that said grapple tongs will bemoved towards said log-grappling position upon said cable beingtensioned.
 11. The invention defined in claim 10 and further including athird pulley bracket vertically pivotally connected to, and projectingtoward said vehicle from, one of said first and second pulley brackets;a third pulley rotatably mounted in said third bracket about an axisextending crosswise to said third bracket pivot axis; and said cablebeing guidingly trained on said third pulley.
 12. The invention definedin claim 10 wherein said first and second tongs each include adjacentand remote ends relative to the distance of the ends from said yoke;said link means pivotally suspending said tongs from said yokecomprising first and second link members respectively having first endspivotally connected to said yoke and having second ends respectivelypivotally connected to said first and second tongs at locations locatedadjacent to, but spaced toward said remote ends from, said adjacent endsof said tongs; said first and second pulley brackets being respectivelypivotally connected to said first and second tongs at locationsintermediate said adjacent ends and the location whereat the second endsof said first and second link members are connected; a first tie linkstructure having a first end pivotally connected to the adjacent end ofsaid first tong and having a second end pivotally connected to thesecond tong coaxially with said second pulley bracket, and a second tielink structure having a first end pivotally connected to the first tongcoaxially with said first pulley bracket and having a second endpivotally connected to said adjacent end of said second tong.
 13. Theinvention defined in claim 12 and further including a third pulleybracket vertically pivotally connected to, and projecting toward saidvehicle from, one of said first and second pulley brackets; a thirdpulley rotatably mounted in said third bracket about an axis extendingcrosswise to said third bracket pivot axis; and said cable beingfuidingly trained on said third pulley.
 14. The invention defined inclaim 12 and further including latch means for selectively locking saidfirst and second tongs in place; said latch means including a pluralityof upwardly facing teeth being spaced along the length of one of saidtie link structures in facing relationship to said yoke; a latch memberbeing pivotally connected, at one end to the adjacent end of that tongto which the tie link structure that carries said teeth is notconnected, for movement toward and away from said teeth and a tang beingformed on said latch member for engagement with said teeth; and remotelyoperable means being connected to said latch member for selectivelymoving the latter so as to place said tang into and out of engagementwith said teeth for respectively locking and unlocking said tongs. 15.The invention defined in claim 14 wherein said remotely actuatable meanscomprises a rod; a swivel being pivotally connected to said yoke midwaybetween the locations whereat said first and second links are connectedto said yoke, said swivel having an opening therethrough extendingcrosswise to the pivotal axis of the block; a rod being slidablereceived in said block; a connector ring being pivotally connected to anupper end of said rod; a link being pivotally connected at one end to alower end of said rod and being pivotally connected at another end tosaid latch member; and said remotely actuatable connector means beingreleasably connected to said connection ring, whereby upward anddownward movement of said boom means when the latter is connected to theconnection ring will respectively cause upward and downward movement ofsaid latch member and thereby effect the unlocking and locking of saidtongs.